st: log transformation question

2 questions:
** 1 **
i am transforming a bunch of variables into their natural logs, and i
have read conflicting advice on how to treat the negative values, such
as growth, which ranges from -99 to +300 in my dataset.
one website suggests i just add +100 to the variable and then log it
gen log_growth = ln(growth+100)
a second website i visited suggests turning all negative values into 0
gen log_growth = ln(growth)
(75 missing values generated)
recode log_growth .=0
** 2 **
once i get all my variables into the appropriate log form, what is the
difference between using regress and cloglog, because they give me
different results.
thank you!
matt
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